Promotional effects of Ce on Ni[sbnd]Ce/γAl2O3 for enhancement of H2 in hydrothermal gasification of biomass

Abstract

This communication presents promotional effects of Ce on a NiCe/γ-Al2O3 catalyst for biomass gasification in hydrothermal reaction conditions. The catalyst samples were prepared by an incipient wetness technique using a successive metal loading approach. The TPR/TPO results showed that the presence of Ce minimized metal support interaction and improved the reducibility and thermal stability of the catalyst. The XRD analysis of fresh and reduced (after 10 repeated TPR/TPO cycles) catalyst samples showed unchanged crystal structures of the nickel particles indicating stable properties of the NiCe/γAl2O3 catalyst. The hydrothermal biomass gasification experiments were conducted using glucose as a biomass surrogate at various reaction temperature (425–525 °C) and time (5–35 min), while the pressure was maintained at 25.5 MPa. It was observed that the addition of Ce influenced the catalyst surface creating more active nickel sites for steam reforming methane reaction. Ce also increased the activity of Ni/γAl2O3 catalysts in terms of hydrogen production by promoting the water gas shift reaction and suppressing the methanation reaction of carbon dioxide.